Question: Solve for $k$ : $-25 + k = -26$
Answer: Add $25$ to both sides: $ \begin{eqnarray} \\ -25 + k &=& -26 \\ \\ {+25} && {+25} \end{eqnarray} $ $ \begin{eqnarray} \hphantom{-25 + k} &\hphantom{=}& \hphantom{-26} \\ k &=& -26 {+ 25} \\ \end{eqnarray} $ Simplify. $ k = -1$